Ractigen's RAG-17 ALS Data Shines at AAN 2025: Earns Top Award, Phase I Advances

Wed, 09 Apr 2025 20:00:00 +0800

• Final results from an Investigator-Initiated Trial presented for the first time, demonstrating favorable safety, significant target engagement, and encouraging clinical & biomarker signals
• Abstract honored with prestigious "Abstracts of Distinction" award by AAN Science Committee, recognizing top quality and interest
• Phase I clinical trial for RAG-17 advancing as planned with dosing successfully completed for the first two cohorts

NANTONG, China and SAN DIEGO, April 9, 2025 /PRNewswire/ -- Ractigen Therapeutics, a clinical-stage biopharmaceutical company focused on developing pioneering RNA-based medicines, today announced that the final, positive results from the Investigator-Initiated Trial (IIT) of RAG-17, a novel siRNA therapy targeting SOD1 for Amyotrophic Lateral Sclerosis (ALS), were presented for the first time during an oral presentation at the American Academy of Neurology (AAN) 2025 Annual Meeting in San Diego, CA.

The presentation, titled "RAG-17 a Novel siRNA Therapy for SOD1-ALS: Safety and Preliminary Efficacy from a First-in-human Trial," was delivered on April 7th by Dr. Weiqi Chen of Beijing Tiantan Hospital, Capital Medical University, on behalf of the team led by the study's Principal Investigator, Dr. Yilong Wang.

Highlighting the significance and quality of the research, the abstract was selected by the AAN Science Committee for the prestigious "Abstracts of Distinction" award. This honor is awarded to abstracts deemed to be the top in their topic category based on the quality of the study and interest to the neurologic community. This follows Ractigen's previous announcement in September 2024 regarding the positive initial clinical data obtained from this IIT study.

Key Findings from the RAG-17 IIT Study Presented at AAN 2025:
The final data from the IIT (NCT05903690), a first-in-human, open-label, dose-escalation study involving six SOD1-ALS patients over 240 days, demonstrated:

• Favorable safety and tolerability: RAG-17 was generally well-tolerated with intrathecal administration. No dose-limiting toxicities (DLTs) or serious adverse events (SAEs) were reported. Most adverse events were mild and transient.
• Significant target engagement: Treatment with RAG-17 led to a substantial reduction of SOD1 protein levels in the cerebrospinal fluid (CSF), exceeding 50% in five out of six subjects, confirming potent target engagement in the central nervous system.
• Substantial reduction in key biomarker: Significant reductions in plasma neurofilament light chain (NfL) levels, a key biomarker of neuroaxonal damage, were observed, suggesting a potential impact on neurodegeneration.
• Encouraging clinical efficacy signals: Patients treated with RAG-17 showed encouraging trends in clinical outcome measures. The average decrease in the ALS Functional Rating Scale-Revised (ALSFRS-R) score was 2.17 points over the study period (equivalent to a 0.29-point decline per month), suggesting potential slowing of functional decline. Forced Vital Capacity (FVC) remained stable in most patients, with two showing a significant increase from baseline.

Phase I Trial Update
Ractigen Therapeutics also reports that a Phase I clinical trial for RAG-17 is progressing smoothly. This randomized, double-blind, placebo-controlled dose escalation study is designed to further evaluate safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary efficacy in SOD1-ALS patients. Following the first patient dosing announced in December 2024, two cohorts have now successfully completed. The trial is being conducted across multiple sites, led by investigators including Dr. Yilong Wang at Beijing Tiantan Hospital, Dr. Zhiying Wu at the Second Affiliated Hospital of Zhejiang University School of Medicine, and Dr. Huifang Shang at West China Hospital, Sichuan University.

"We are thrilled that our RAG-17 program has been honored with an Abstract of Distinction at the AAN 2025 meeting. This recognition highlights the significance of our work in addressing the unmet needs of SOD1-ALS patients," said Dr. Long-Cheng Li, President and CEO of Ractigen Therapeutics. "The positive final data from our IIT, demonstrating favorable safety, robust target knockdown, and encouraging biomarker and clinical signals, combined with the ongoing progress in our Phase I trial, reinforce our commitment to bringing this innovative therapy to those who need it most."

Dr. Yilong Wang, Principal Investigator of the RAG-17 IIT study and Vice President of Beijing Tiantan Hospital, Capital Medical University, commented, "The results presented at AAN 2025 demonstrate the potential of RAG-17 to significantly impact the lives of patients with SOD1-ALS. The safety profile and early efficacy signals, particularly the significant reduction in CSF SOD1 and plasma NfL levels alongside stable functional measures, are encouraging. We look forward to continuing our work in the Phase I study to further validate these findings and bring this therapy closer to clinical application."

About RAG-17
RAG-17 is an investigational siRNA therapeutic candidate designed using Ractigen's proprietary SCAD™ delivery platform technology to specifically target and silence the superoxide dismutase 1 (SOD1) gene mRNA. Mutations in the SOD1 gene cause a toxic gain-of-function and are a known cause of familial Amyotrophic Lateral Sclerosis (ALS). By reducing the production of the toxic mutant SOD1 protein, RAG-17 aims to slow or halt the progression of SOD1-ALS.

About ALS
Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease affecting nerve cells in the brain and spinal cord, leading to muscle weakness, paralysis, and ultimately death, typically within three to five years of diagnosis. SOD1 gene mutations account for approximately 10-20% of familial ALS cases and about 1-2% of sporadic ALS cases. There remains a critical unmet medical need for effective treatments that can slow or stop disease progression.

About Ractigen Therapeutics 
Ractigen Therapeutics is a clinical-stage biopharmaceutical company innovating next-generation RNA therapeutics, with a primary focus on small activating RNAs (saRNAs) developed through its clinically validated RNA activation (RNAa) technology. Leveraging proprietary delivery platforms such as SCAD™, LiCO™, and GLORY™, Ractigen is advancing a robust pipeline addressing unmet medical needs in oncology, neurological diseases, and genetic disorders. Its versatile technologies also enable the rapid development of RNA-based solutions, including siRNAs, where applicable, to target life-threatening, fast-progressing conditions such as those in the CNS. Committed to scientific excellence and patient-centered innovation, Ractigen strives to transform healthcare through the power of RNA therapeutics. For more information, visit www.ractigen.com.